1. Field of the Invention
The present invention relates to a fuel cell and a fuel cell system having the fuel cell.
2. Description of the Related Art
The fuel cell is an electricity generating system for directly converting chemical reaction energy of hydrogen contained in a fuel and oxygen which is provided separately from the fuel into electrical energy.
The fuel cell is classified into various types of fuel cells according to components constructing the fuel cell or types of fuel used in the fuel cell. A monopolar fuel cell, which is constructed with a plurality of unit cells which are two-dimensionally disposed, provides fuel and oxygen to the unit cells in order to generate electrical energy.
The monopolar fuel cell known in the art is supplied with oxygen through one side of the fuel cell main body constructed with the unit cells. Supplying oxygen through only one side of the fuel cell main body does not allow the fuel cell to operate at its maximum efficiency and makes it difficult to cool the unit cells, which emit heat. Therefore, supplying oxygen through only one side of the fuel cell main body reduces the fuel cell performance reliability and increases the safety danger to users of the fuel cell.
Recently, lightweight, compact, and high-tech electronic devices such as a telecommunication mobile terminal, a portable multimedia player (PMP), a playstation portable (PSP), and a personal digital assistants (PDA) have been developed.
As a power source of the electronic device, rechargeable batteries are generally used. However, existing rechargeable batteries cannot cope with the high power consumption of the recently developed electronic devices.
Therefore, in the fuel cell art, a fuel cell system which can maximize an output of electrical energy and can be easily used and carried with the electronic device is required.